Slightly more efficient loop in flush_neighbour_routes.
Slightly more efficient loop in flush_neighbour_routes.

woniullb/babeld,tcatm/babeld,wlanslovenija/babeld,Gwendocg/babeldToS,jech/babeld,Gwendocg/babeldToS,jech/babeld,wlanslovenija/babeld,dtaht/babeld-shortrtt-metrics,sudomesh/babeld,Drooids/babeld,boutier/babeld